Orientador: Fernando Lucas Primo / Resumo: Os materiais nanoestruturados têm potencial diferente em comparação com outros materiais em maior escala, resultando em diferentes características e propriedades físico-químicas. Inicialmente foram preparadas nanoemulsões (NE) contendo corante vermelho (CV) um derivado de antraquinona, produzido pelo cultivo do fungo Talaromyces minioluteus em mesa incubadora rotativa, no entanto as NE com corante vermelho (CV/NE) não apresentaram características físico-químicas desejadas (tamanho de partícula ≤ 250 nm, índice de polidispersividade ≤0,3), partindo-se então para a utilização de nanocápsulas poliméricas (NC) como sistemas carreadores para este ativo. Foram preparadas amostras de NC vazias (Vazia/NC), com corante vermelho (CV/NC), com corante vermelho associado a ftalocianina de cloro alumínio (CV_ClAlPc/NC) e somente com ftalocianina de cloro alumínio (ClAlPc/NC). Estes nanomateriais foram caracterizados e apresentaram características físico- químicas adequadas, com tamanho de partícula < 250 nm, índice de polidispersividade ≤ 0,3 e potencial Zeta predominantemente negativo. As análises de estabilidade acelerada apresentaram um tempo vida de armazenamento > 3 meses para todas as NC. As análises de microscopia por força atômica (MFA) realizadas para CV/NC e CV_ClAlPc/NC mostram uma morfologia esférica para ambas as NC e tamanho de partícula de 104 nm para CV/NC e 211nm para CV_ClAlPc/NC, as análises por diferença de fase mostraram que a superfície da partícula é homogênea, ou se... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Nanostructured materials have different potential compared to other materials on a larger scale, resulting in different physico-chemical characteristics and properties. Initially NE were prepared containing red dye (RD) an anthraquinone derivative produced by cultivating the Talaromyces minioluteus fungus on rotary incubator table. However, the RD/NE have not shown the desired physical-chemical characteristics, starting with the use of nanocapsules as carrier systems for this active. Empty NC samples (blank / NC), with red dye (RD / NC), with red dye associated with phthalocyanine chlorine aluminum (RD_ClAlPc / NC) and with phthalocyanine chlorine aluminum (ClAlPc / NC) were prepared. These nanomaterials were characterized and presented adequate physico-chemical characteristics, with particle size <250 nm, polydispersity index ≤ 0.3 and Zeta potential predominantly negative. The accelerated stability analyzes showed a shelf life> 3 months for all NCs. Atomic force microscopy (MFA) analyzes performed for RD / NC and RD_ClAlPc / NC show a spherical morphology for both NC and particle size of 104 nm for RD / NC and 211nm for RD_ClAlPc / NC. The difference analysis of phase showed that the particle surface is homogeneous, that is, composed only of polylactic-co-glycolic acid (PLGA) and it is possible to affirm that there is no free active in the NC medium. UV-visible spectroscopic absorption and emission spectroscopic analyzes were performed which did not show changes in the free... (Complete abstract click electronic access below) / Mestre

O meio hidrotrópico tem sido intensamente explorado pela indústria a fim de melhorar a solubilização de substâncias pouco solúveis em água. Os hidrótropos são compostos anfifílicos, como os surfactantes, mas os microdomínios formados não têm estruturas bem organizadas como as micelas. O mecanismo de solubilização hidrotrópica não está completamente elucidado. Muitos esforços têm sido feitos nesse sentido tanto em nosso grupo quanto por outros pesquisadores. Os alginatos também formam microdomínios em solução e tem sido bastante estudados devido a suas aplicações na agricultura, farmácia, medicina, dentre outras. Sabe-se que as propriedades fotofísicas de corantes são sensíveis ao meio no qual eles se encontram. Neste trabalho as propriedades fotofísicas do corante pseudoisocianina (PIC) foram determinadas em soluções hidrotrópicas de toluenossulfonato de sódio (TSS) e estirenossulfonato de sódio (ESS), em soluções de metanol, etanol, butanol e etilenoglicol, bem como em solução aquosa de alginato de sódio. Estes estudos também agregam informações para a compreensão do comportamento dos hidrótropos em solução aquosa, usando-se o corante PIC como sonda fotofísica. / Hydrotropic media have been intensively explored by industry to improve the solubilization of poorly water-soluble substances. Hydrotropes are amphiphilic compounds, such as surfactants, that form microdomains that are not as wellorganized as micelles. The mechanism of hydrotropic solubilization is not completely elucidated. Much effort has been done towards this end, in our group and by other researchers. Alginates also form microdomains in solution and have been largely studied due to their applications in agriculture, pharmacy, medicine, among others. It is well-known that the photophysical properties of dyes depend on the environment in which they are placed. In this work, photophysical properties of the dye pseudoisocyanine (PIC) have been determined in hydrotropic solutions of sodium toluenesulphonate (TSS) and sodium styrenesulphonate (ESS), in solutions of methanol, ethanol, butanol and etileneglycol, as well as in sodium alginate aqueous solution. This study also adds information to the understanding of hydrotrope behaviour in aqueous solution by using PIC as a photophysical probe.

O meio hidrotrópico tem sido intensamente explorado pela indústria a fim de melhorar a solubilização de substâncias pouco solúveis em água. Os hidrótropos são compostos anfifílicos, como os surfactantes, mas os microdomínios formados não têm estruturas bem organizadas como as micelas. O mecanismo de solubilização hidrotrópica não está completamente elucidado. Muitos esforços têm sido feitos nesse sentido tanto em nosso grupo quanto por outros pesquisadores. Os alginatos também formam microdomínios em solução e tem sido bastante estudados devido a suas aplicações na agricultura, farmácia, medicina, dentre outras. Sabe-se que as propriedades fotofísicas de corantes são sensíveis ao meio no qual eles se encontram. Neste trabalho as propriedades fotofísicas do corante pseudoisocianina (PIC) foram determinadas em soluções hidrotrópicas de toluenossulfonato de sódio (TSS) e estirenossulfonato de sódio (ESS), em soluções de metanol, etanol, butanol e etilenoglicol, bem como em solução aquosa de alginato de sódio. Estes estudos também agregam informações para a compreensão do comportamento dos hidrótropos em solução aquosa, usando-se o corante PIC como sonda fotofísica. / Hydrotropic media have been intensively explored by industry to improve the solubilization of poorly water-soluble substances. Hydrotropes are amphiphilic compounds, such as surfactants, that form microdomains that are not as wellorganized as micelles. The mechanism of hydrotropic solubilization is not completely elucidated. Much effort has been done towards this end, in our group and by other researchers. Alginates also form microdomains in solution and have been largely studied due to their applications in agriculture, pharmacy, medicine, among others. It is well-known that the photophysical properties of dyes depend on the environment in which they are placed. In this work, photophysical properties of the dye pseudoisocyanine (PIC) have been determined in hydrotropic solutions of sodium toluenesulphonate (TSS) and sodium styrenesulphonate (ESS), in solutions of methanol, ethanol, butanol and etileneglycol, as well as in sodium alginate aqueous solution. This study also adds information to the understanding of hydrotrope behaviour in aqueous solution by using PIC as a photophysical probe.

Foram sintetizadas duas novas classes de porfirinas aquosolúveis pela quaternização dos resíduos piridínicos da TPyP empregando halelos de benzila e alila. Os produtos dessas reações de quaternização TBzPyP e TAlPyP. são mais facilmenle obtidos que a TMPyP, exingindo menores tempos de reação e menores quantidades de agente alquilante para que a quaternização total da TPyP seja efetuada. Esse procedimento surge como uma rota alternativa para a obtenção de porfirinas aquosolúvei s e vale-se da alta estabilidade dos cátions benzílicos e alílicos. Os respectivos complexos de zinco e paládio foram obtidos da reação de quaternização de ZnTPyP e PdTPyP ou por reações de metalação de TBzPyP e TAlPyP. As bases livres e os metalocomplexos foram estudados quanto às suas propriedades espectroscópicas, eletroquímicas e fotoquímicas. Os novos derivados apresentam deslocamentos batocrômicos das posições dos máximos de absorção e emissão se comparados com a série metil-piridil substituída, indicando a existência de efeitos eletrônicos e vibracionais dos substituintes sobre o sistema &#928; do macrociclo. Os dados espectroscópicos mostram evidências de que as bases livres encontram-se em solução aquosa no estado agregado, provavelmenle formando dímeros em concentrações superiores a cerca de 6.0 x 10-7 M. A presença de detergentes aniônicos altera significamente tanto a posição dos máximos de absorção como de emissão mostrando que além dos aspectos eletrostáticos fatores hidrofôbicos-hidrofílicos fazem-se presentes na interação de surfactantes com os derivados porfirínicos. C comportamento eletroquímico dos derivados benzílicos e alílicos também é diferenciado com relação aos derivados metílicos, sendo observadas maiores separações entre os picos anódico e catódico. Estas diferenças devem-se, provavelmente ao maior caráter hidrofóbico destes derivados, que originam interações específicas nos processos eletródicos. Os tempos de vida do estado excitado triplete das zinco porfirinas, ZnTMPyP, ZnTBzPyP e ZnTAlPyP foram medidos utilizando-se a técnica de flash-photolysis, sendo que todas apresentam tempos de vida da ordem de 1 ms. A fim de estudar reações de transferência de elétrons fotoinduzidas entre os novos derivados porfirínicos e aceptores adequados em sistemas de clivagem da água (p. ex. metilviologênio), catalisadores coloidais de platina foram preparados pela redução de Pt(IV) ou Pt(II) a Pt(O), e as dimensões do colóide foram estimadas por microscopia eletrônica, sendo obtidas partículas coloidais de 30-40 &#197;. A concentração de platina foi determinada por emissão atômica, ou por complexiometria. Estudou-se a interação de porfirinas e metaloporfirinas com o polímero sintético da melanina, utilizando-se a técnica de emissão de fluorescência. Verificou-se que a presença de metais coordenados à porfirina assim como a presença de grupos com maior caráter hidrofôbico acentuam a interação implicando em maior especificidade destes derivados, característica essa apropriada para a utilização destas moléculas em terapia fotodinâmica. Foi determinada a CMC em pH = 1,00 de um derivado porfirínico surfactante, sendo que a partir de 1,0 x 10-4 M ocorre a micelização. Este é o primeiro exemplo de auto-agregação de uma porfirina sintética em um meio onde não participam solventes orgânicos. / In the present work two new classes of water soluble porphyrins were prepared by the quaternization of the TPyP pyridynic groups employng benzyl and allyl halides. The products of these quaternization reactions, TBzPyP and TAlPyP, are easier to obtain than TMPyP because they require smaller amounts of alkylating agents and a less period of reaction to achive the pyridinic quaternization. This method is an alternative route in obtaining water soluble porphyrins and is based on the high stability of the benzylic and allylic cation. The corresponding zinc and palladium complexes were obtanained by quaternization reactions of ZnTPyP and PdTPyP or by metallation reactions of TBzPyP and TAlPyP. The free bases and metallocomplexes studies were carried out taking to account their spectroscopic electrochemical and photochemical properties. The new derivatives exhibit bathocromic shifts in the absorption and emission position bands when compared with the methyl-pyridynium derivatives these data indicate the existence of elect.ronic and vibrational effects of the substituents on the macrociclic &#928; system. The espectroscopic data show evidences that the free bases are like aggregates in aqueous solution, probably forming dimers in the concentration range of 5,0 x 10-7 M. The presence of anionic detergents alter deeply the spectroscopic properties, showing that hidrophobic-hidrophylic factors in addition of eletrostatic factors are present, in the interaction of the surfactant with the porphyrinic derivatives. The electrochemical behavior of the benzylic and allylic derivatives are different when compared with the methylic derivatives, were it was observed greater separation between the anodic and cathodic peaks. The observed differences are probably due to specific interactions of the more hidrophobic derivatives in eletrode processes. The triplet excited state lifetimes of the zinc derivatives, ZnTMPyP, ZnTBzPyP e ZnTAlPyP mesured employng f\'lash-photolysis thecnics were c.a. 1 ms. The synthesis of coloidal platinum catalyst was achived by slight modification of the literature methods, and the size of the majority particules determined by electron microscopy are around 30-40 A. The int.eract.ion between porphyrins and metalloporphyrins wilh the synthetic melanin polymer was studied employng fluorescence emisson. The presence of coordinate metals and the presence of more hidrophobic groups attached at the porphyrin ring originate greater specificity by the polymer, which make them possible photosensitizers in photodynamic therapy. It was also determined the CMC of a surfactant funtionalyzed zinc porphyrin in aqueous medium at. pH = 1,00. This derivative form micellar assemblies at 1,0 x 10-4 M, and is the first example of self aggregation of a synthetic porphyrin in a non-organic medium.

Foram sintetizadas duas novas classes de porfirinas aquosolúveis pela quaternização dos resíduos piridínicos da TPyP empregando halelos de benzila e alila. Os produtos dessas reações de quaternização TBzPyP e TAlPyP. são mais facilmenle obtidos que a TMPyP, exingindo menores tempos de reação e menores quantidades de agente alquilante para que a quaternização total da TPyP seja efetuada. Esse procedimento surge como uma rota alternativa para a obtenção de porfirinas aquosolúvei s e vale-se da alta estabilidade dos cátions benzílicos e alílicos. Os respectivos complexos de zinco e paládio foram obtidos da reação de quaternização de ZnTPyP e PdTPyP ou por reações de metalação de TBzPyP e TAlPyP. As bases livres e os metalocomplexos foram estudados quanto às suas propriedades espectroscópicas, eletroquímicas e fotoquímicas. Os novos derivados apresentam deslocamentos batocrômicos das posições dos máximos de absorção e emissão se comparados com a série metil-piridil substituída, indicando a existência de efeitos eletrônicos e vibracionais dos substituintes sobre o sistema &#928; do macrociclo. Os dados espectroscópicos mostram evidências de que as bases livres encontram-se em solução aquosa no estado agregado, provavelmenle formando dímeros em concentrações superiores a cerca de 6.0 x 10-7 M. A presença de detergentes aniônicos altera significamente tanto a posição dos máximos de absorção como de emissão mostrando que além dos aspectos eletrostáticos fatores hidrofôbicos-hidrofílicos fazem-se presentes na interação de surfactantes com os derivados porfirínicos. C comportamento eletroquímico dos derivados benzílicos e alílicos também é diferenciado com relação aos derivados metílicos, sendo observadas maiores separações entre os picos anódico e catódico. Estas diferenças devem-se, provavelmente ao maior caráter hidrofóbico destes derivados, que originam interações específicas nos processos eletródicos. Os tempos de vida do estado excitado triplete das zinco porfirinas, ZnTMPyP, ZnTBzPyP e ZnTAlPyP foram medidos utilizando-se a técnica de flash-photolysis, sendo que todas apresentam tempos de vida da ordem de 1 ms. A fim de estudar reações de transferência de elétrons fotoinduzidas entre os novos derivados porfirínicos e aceptores adequados em sistemas de clivagem da água (p. ex. metilviologênio), catalisadores coloidais de platina foram preparados pela redução de Pt(IV) ou Pt(II) a Pt(O), e as dimensões do colóide foram estimadas por microscopia eletrônica, sendo obtidas partículas coloidais de 30-40 &#197;. A concentração de platina foi determinada por emissão atômica, ou por complexiometria. Estudou-se a interação de porfirinas e metaloporfirinas com o polímero sintético da melanina, utilizando-se a técnica de emissão de fluorescência. Verificou-se que a presença de metais coordenados à porfirina assim como a presença de grupos com maior caráter hidrofôbico acentuam a interação implicando em maior especificidade destes derivados, característica essa apropriada para a utilização destas moléculas em terapia fotodinâmica. Foi determinada a CMC em pH = 1,00 de um derivado porfirínico surfactante, sendo que a partir de 1,0 x 10-4 M ocorre a micelização. Este é o primeiro exemplo de auto-agregação de uma porfirina sintética em um meio onde não participam solventes orgânicos. / In the present work two new classes of water soluble porphyrins were prepared by the quaternization of the TPyP pyridynic groups employng benzyl and allyl halides. The products of these quaternization reactions, TBzPyP and TAlPyP, are easier to obtain than TMPyP because they require smaller amounts of alkylating agents and a less period of reaction to achive the pyridinic quaternization. This method is an alternative route in obtaining water soluble porphyrins and is based on the high stability of the benzylic and allylic cation. The corresponding zinc and palladium complexes were obtanained by quaternization reactions of ZnTPyP and PdTPyP or by metallation reactions of TBzPyP and TAlPyP. The free bases and metallocomplexes studies were carried out taking to account their spectroscopic electrochemical and photochemical properties. The new derivatives exhibit bathocromic shifts in the absorption and emission position bands when compared with the methyl-pyridynium derivatives these data indicate the existence of elect.ronic and vibrational effects of the substituents on the macrociclic &#928; system. The espectroscopic data show evidences that the free bases are like aggregates in aqueous solution, probably forming dimers in the concentration range of 5,0 x 10-7 M. The presence of anionic detergents alter deeply the spectroscopic properties, showing that hidrophobic-hidrophylic factors in addition of eletrostatic factors are present, in the interaction of the surfactant with the porphyrinic derivatives. The electrochemical behavior of the benzylic and allylic derivatives are different when compared with the methylic derivatives, were it was observed greater separation between the anodic and cathodic peaks. The observed differences are probably due to specific interactions of the more hidrophobic derivatives in eletrode processes. The triplet excited state lifetimes of the zinc derivatives, ZnTMPyP, ZnTBzPyP e ZnTAlPyP mesured employng f\'lash-photolysis thecnics were c.a. 1 ms. The synthesis of coloidal platinum catalyst was achived by slight modification of the literature methods, and the size of the majority particules determined by electron microscopy are around 30-40 A. The int.eract.ion between porphyrins and metalloporphyrins wilh the synthetic melanin polymer was studied employng fluorescence emisson. The presence of coordinate metals and the presence of more hidrophobic groups attached at the porphyrin ring originate greater specificity by the polymer, which make them possible photosensitizers in photodynamic therapy. It was also determined the CMC of a surfactant funtionalyzed zinc porphyrin in aqueous medium at. pH = 1,00. This derivative form micellar assemblies at 1,0 x 10-4 M, and is the first example of self aggregation of a synthetic porphyrin in a non-organic medium.

Dans un contexte où l’approvisionnement énergétique mondial du 21e siècle est un enjeu majeur, le développement de sources d’énergie renouvelables suscite l’attention croissante de la communauté scientifique et industrielle. L’énergie solaire est définitivement l’une des meilleures alternatives aux combustibles fossiles en tant que source d’énergie du monde de demain. Ce mémoire traite donc du développement de nouveaux matériaux organométalliques pour des applications de photorécoltage d’énergie en photovoltaïque et en production d’hydrogène. Le premier chapitre présente la synthèse assistée par microondes de quatre nouveaux complexes de Co(II), Ni(II), Cu(II) et Zn(II) basés sur le ligand tétra-p-méthoxyphényl-azadipyrrométhène (ADPM) avec des rendements variant de 89% à quantitatif. Ces complexes sont mis en relation avec d’autres complexes homoleptiques connus portant le tétraphényl-ADPM comme ligand ainsi qu’avec leurs chélates de BF2+ pour une meilleure compréhension des tendances engendrées par la substitution de l’agent coordonnant et/ou des substituants p-méthoxy. Pour ce faire, le comportement électrochimique et photophysique est présenté. De façon générale, la présence des quatre groupements p-méthoxy semble rendre les dérivés de cet ADPM plus susceptibles à la dégradation électrochimique en conditions d’oxydation et induire un déplacement bathochromique des propriétés optiques d’absorption et d’émission. Les structures rayons X du ligand tétra-p-méthoxyphényl-ADPM et de son complexe homoleptique de Co(II) sont aussi discutées. Cette étude a été effectuée dans l’espoir de fournir des informations utiles sur la stabilité des ADPM aux chercheurs du domaine photovoltaïque en quête de nouveaux chromophores dans le proche infrarouge (NIR). Le deuxième chapitre présente quant à lui les propriétés de senseur envers les anions F-, OAc- et H2PO4- de deux nouveaux complexes neutres de Re(I) de type mono- et dinucléaire basés sur une phénanthroline substituée en position 5 contenant un récepteur thio-urée. Ces composés ont été obtenus dans des rendements de 81% et 60%, respectivement. L’effet de la formation de ponts hydrogène lors de l’ajout d’anions versus la déprotonation du récepteur a été évalué par des titrations UV/Vis et RMN 1H et semble indiquer que la formation de la base conjuguée du récepteur est favorisée pour ce type de système. De plus, la structure rayons X d’un des précurseurs est présentée et permet une discussion sur la chiralité des complexes mono- et dinucléaire obtenus. L’obtention d’un complexe bimétallique par autoassemblage ouvre la voie à la préparation d’antennes moléculaires pour des systèmes de photosynthèse artificielle. / The world's energy supply is rapidly becoming the major issue of the 21st century. Instead of the status quo approach of finding and extracting more hydrocarbons from the ground, the development of renewable energy sources is attracting much interest from both the scientific and industrial communities. Solar energy is definitively one of the best sources to power the World of tomorrow. In such a framework, this dissertation discusses the development of new organometallic materials able to harvest solar energy for photovoltaic or H2 photoproduction applications. The first chapter presents the synthesis by a microwaves-assisted methodology of four new homoleptic complexes of Co(II), Ni(II), Cu(II) and Zn(II) based on the tetra-p-methoxyphenyl-azadipyrromethene (ADPM) ligand in yields ranging from 89% to quantitative. Those complexes are put in relation with already known ADPM homoleptic complexes of the same M(II) series and related BF2+ chelates (Aza-BODIPY) for a better understanding of trends arising from substitution of the chelate and/or electron-donating effect of the p-methoxy substituents. This is achieved by the study of electrochemical behavior of the compounds and their photophysical properties. From a general point of view, the presence of the four p-methoxy substituents leads to an electrochemical decomposition of the derivatives based on that ADPM in oxidative conditions, along with a bathochromic shift of the optical properties. X-Ray structures for the tetra-p-methoxyphenyl-ADPM ligand and related Co(II) complex are also discussed. Hopefully, this study will provide useful insights to researchers on the substituents to install for stable ADPM derivatives in their quest for NIR chromophores utilizable for photovoltaic application. The second chapter report anion sensing properties toward F-, OAc- and H2PO4- of new neutral mononuclear and dinuclear Re(I) complexes based on a 5-substituted phenanthroline moiety bearing a thiourea hydrogen-bonding receptor. Those complexes were obtained in 81% and 60% yields, respectively. The effect of hydrogen-bonding versus deprotonation of the thiourea receptor upon addition of the anions was also evaluated by UV/vis and 1H NMR titration techniques. Observations made support the hypothesis that formation of the conjugated base of the receptor is favored. In addition, an X-ray structure of the Re(I) precursor complex is reported and the chirality of the mononuclear and dinuclear complexes is discussed. Achievement of a bimetallic complex by self-assembly paves the way for the preparation of light-harvesting molecular antennae utilizable in artificial photosynthesis systems.

Dans un contexte où l’approvisionnement énergétique mondial du 21e siècle est un enjeu majeur, le développement de sources d’énergie renouvelables suscite l’attention croissante de la communauté scientifique et industrielle. L’énergie solaire est définitivement l’une des meilleures alternatives aux combustibles fossiles en tant que source d’énergie du monde de demain. Ce mémoire traite donc du développement de nouveaux matériaux organométalliques pour des applications de photorécoltage d’énergie en photovoltaïque et en production d’hydrogène. Le premier chapitre présente la synthèse assistée par microondes de quatre nouveaux complexes de Co(II), Ni(II), Cu(II) et Zn(II) basés sur le ligand tétra-p-méthoxyphényl-azadipyrrométhène (ADPM) avec des rendements variant de 89% à quantitatif. Ces complexes sont mis en relation avec d’autres complexes homoleptiques connus portant le tétraphényl-ADPM comme ligand ainsi qu’avec leurs chélates de BF2+ pour une meilleure compréhension des tendances engendrées par la substitution de l’agent coordonnant et/ou des substituants p-méthoxy. Pour ce faire, le comportement électrochimique et photophysique est présenté. De façon générale, la présence des quatre groupements p-méthoxy semble rendre les dérivés de cet ADPM plus susceptibles à la dégradation électrochimique en conditions d’oxydation et induire un déplacement bathochromique des propriétés optiques d’absorption et d’émission. Les structures rayons X du ligand tétra-p-méthoxyphényl-ADPM et de son complexe homoleptique de Co(II) sont aussi discutées. Cette étude a été effectuée dans l’espoir de fournir des informations utiles sur la stabilité des ADPM aux chercheurs du domaine photovoltaïque en quête de nouveaux chromophores dans le proche infrarouge (NIR). Le deuxième chapitre présente quant à lui les propriétés de senseur envers les anions F-, OAc- et H2PO4- de deux nouveaux complexes neutres de Re(I) de type mono- et dinucléaire basés sur une phénanthroline substituée en position 5 contenant un récepteur thio-urée. Ces composés ont été obtenus dans des rendements de 81% et 60%, respectivement. L’effet de la formation de ponts hydrogène lors de l’ajout d’anions versus la déprotonation du récepteur a été évalué par des titrations UV/Vis et RMN 1H et semble indiquer que la formation de la base conjuguée du récepteur est favorisée pour ce type de système. De plus, la structure rayons X d’un des précurseurs est présentée et permet une discussion sur la chiralité des complexes mono- et dinucléaire obtenus. L’obtention d’un complexe bimétallique par autoassemblage ouvre la voie à la préparation d’antennes moléculaires pour des systèmes de photosynthèse artificielle. / The world's energy supply is rapidly becoming the major issue of the 21st century. Instead of the status quo approach of finding and extracting more hydrocarbons from the ground, the development of renewable energy sources is attracting much interest from both the scientific and industrial communities. Solar energy is definitively one of the best sources to power the World of tomorrow. In such a framework, this dissertation discusses the development of new organometallic materials able to harvest solar energy for photovoltaic or H2 photoproduction applications. The first chapter presents the synthesis by a microwaves-assisted methodology of four new homoleptic complexes of Co(II), Ni(II), Cu(II) and Zn(II) based on the tetra-p-methoxyphenyl-azadipyrromethene (ADPM) ligand in yields ranging from 89% to quantitative. Those complexes are put in relation with already known ADPM homoleptic complexes of the same M(II) series and related BF2+ chelates (Aza-BODIPY) for a better understanding of trends arising from substitution of the chelate and/or electron-donating effect of the p-methoxy substituents. This is achieved by the study of electrochemical behavior of the compounds and their photophysical properties. From a general point of view, the presence of the four p-methoxy substituents leads to an electrochemical decomposition of the derivatives based on that ADPM in oxidative conditions, along with a bathochromic shift of the optical properties. X-Ray structures for the tetra-p-methoxyphenyl-ADPM ligand and related Co(II) complex are also discussed. Hopefully, this study will provide useful insights to researchers on the substituents to install for stable ADPM derivatives in their quest for NIR chromophores utilizable for photovoltaic application. The second chapter report anion sensing properties toward F-, OAc- and H2PO4- of new neutral mononuclear and dinuclear Re(I) complexes based on a 5-substituted phenanthroline moiety bearing a thiourea hydrogen-bonding receptor. Those complexes were obtained in 81% and 60% yields, respectively. The effect of hydrogen-bonding versus deprotonation of the thiourea receptor upon addition of the anions was also evaluated by UV/vis and 1H NMR titration techniques. Observations made support the hypothesis that formation of the conjugated base of the receptor is favored. In addition, an X-ray structure of the Re(I) precursor complex is reported and the chirality of the mononuclear and dinuclear complexes is discussed. Achievement of a bimetallic complex by self-assembly paves the way for the preparation of light-harvesting molecular antennae utilizable in artificial photosynthesis systems.

Ce projet de recherche mené en collaboration industrielle avec St-Jean Photochimie Inc. / PCAS Canada vise le développement et la caractérisation de dérivés dipyrrométhène pour des applications dans le domaine du photovoltaïque. La quête du récoltage des photons se situant dans le proche-infrarouge a été au centre des modifications structurales explorées afin d’augmenter l’efficacité de conversion des cellules solaires de type organique et à pigments photosensibles. Trois familles de composés intégrant le motif dipyrrométhène ont été synthétisées et caractérisées du point de vue spectroscopique, électrochimique, structural ainsi que par modélisation moléculaire afin d’établir des relations structures-propriétés. La première famille comporte six azadipyrrométhènes au potentiel de coordination tétradentate sur des centres métalliques. Le développement d’une nouvelle voie synthétique asymétrique combinée à l’utilisation d’une voie symétrique classique ont permis d’obtenir l’ensemble des combinaisons de substituants possibles sur les aryles proximaux incluant les noyaux 2-hydroxyphényle, 2-méthoxyphényle et 2- pyridyle. La modulation du maximum d’absorption dans le rouge a pu être faite entre 598 et 619 nm. De même, la présence de groupements méthoxyle ou hydroxyle augmente l’absorption dans le violet (~410 nm) tel que démontré par modélisation. La caractérisation électrochimique a montré que les dérivés tétradentates étaient en général moins stables aux processus redox que leur contre-parti bidentate. La deuxième famille comporte dix dérivés BODIPY fusionnés de façon asymétrique en position [b]. L’aryle proximal a été modifié de façon systématique afin de mieux comprendre l’impact des substituents riches en électron et de la fusion de cycles aromatiques. De plus, ces dérivés ont été mis en relation avec une vaste série de composés analogues. Les résultats empiriques ont montré que les propriétés optoélectroniques de la plateforme sont régies par le degré de communication électronique entre l’aryle proximal, le pyrrole sur lequel il est attaché et le noyau indolique adjacent à ce dernier. Les maximums d’absorption dans le rouge sont modulables entre 547 et 628 nm et la fluorescence des composés se situe dans le proche- infrarouge. L’un des composé s’est révélé souhaitable pour une utilisation en photovoltaïque ainsi qu’à titre de sonde à pH. La troisième famille comporte cinq complexes neutres de RuII basés sur des polypyridines et portant un ligand azadipyrrométhène cyclométalé. Les composés ont montré une forte absorption de photons dans la région de 600 à 800 nm (rouge à proche- infrarouge) et qui a pu être étendue au-delà de 1100 nm dans le cas des dérivés portant un ligand terpyridine. L’analyse des propriétés optoélectroniques de façon empirique et théorique a montré un impact significatif de la cyclométalation et ouvert la voie pour leur étude en tant que photosensibilisateurs en OPV et en DSSC. La capacité d’un des complexes à photo-injecter un électron dans la bande de conduction du semi-conducteur TiO2 a été démontré en collaboration avec le groupe du Pr Gerald J. Meyer à University of North Carolina at Chapel Hill, premier pas vers une utilisation dans les cellules solaires à pigments photosensibles. La stabilité des complexes en solution s’est toutefois avérée problématique et des pistes de solutions sont suggérées basées sur les connaissances acquises dans le cadre de cette thèse. / This research project carried out in industrial collaboration with Saint-Jean Photochemicals Inc. / PCAS Canada aims at the development and characterization of dipyrromethene derivatives for photovoltaic applications. The quest for harvesting near- infrared photons was the central focus and various structural modifications were explored to improve the power conversion efficiency of organic and dye-sensitized solar cells (OPV and DSSC, respectively). Three families of chromophores which embedded a dipyrromethene motif were synthesized and characterized through spectroscopy, electrochemistry, X-ray diffraction and computationnal modelization in order to establish their structure-properties relationship. The first family includes six azadipyrromethenes with potential for tetradentate coordination on metallic centers. The development of a new asymmetric synthetic route together with the classical symmetric one allowed access to all possible combinations of derivatives including 2-hydroxyphenyl, 2-methoxyphenyl and 2-pyridyl substituents in the proximal position of the dipyrromethene. Modulation of the absorption maxima in the red ranged between 598 and 619 nm. Also, having methoxy or hydroxy substituents provided an increase of the violet absorption (~410 nm) as established by modelization. Electrochemical characterization showed that the tetradentate azadipyrromethenes were generally less stable towards redox processes as compared to their bidentate counter- parts. The second family includes ten asymmetric benzo[b]-fused BODIPYs where the proximal aryl was systematically modified in order to assess the impact of electron-rich substituents and fused aromatic cycles. The derivatives were further compared to a wide series of related BODIPYs. Empirical results showed the optoelectronic properties are dictated by the extend of electronic communication between the proximal aryl, the pyrrol to which it is attached and the adjacent indolic moiety. Absorption maxima in the red were modulated between 547 nm and 628 nm and the fluorescence was in the near-infrared. One compound proved to be a potential candidate for photovoltaic and pH probe applications. The third family includes five neutral RuII polypyridine complexes bearing a cyclometalated azadipyrromethene ligand. The compounds exhibit strong light absorption in the 600 – 800 nm range (red to near-infrared) that tails beyond 1100 nm in the terpyridine-based adducts. Analysis of the optoelectronic properties showed a significant impact of this novel cyclometalation strategy for dipyrromethene derivatives and paved the way for further incorporation of the resulting complexes as photosensitizers in OPV and DSSC. In collaboration with the group of Pr Gerald J. Meyer at the University of North Carolina at Chapel Hill, the capacity of one compound to photo-inject its electron into the conduction band of the TiO2 semiconductor was established, a first step towards their use in dye-sensitized solar cells. The structural instability in solution of the complexes hindered their full potential for photovoltaic applications and suggestions to improve them are proposed based on the knowledge acquired in the course of this thesis.

Dans un contexte où l’énergie représente un enjeu majeur pour les pays et organisations à économies émergentes et développées, la recherche de nouvelles sources renouvelables et la démocratisation des vecteurs énergétiques permettant l’approvisionnement mondial de façon durable constitue un devoir pour la communauté scientifique internationale. D’ailleurs, il serait essentiel que les nombreuses disciplines de la chimie concertent leurs efforts. Plus particulièrement, la croissance de la recherche en chimie de coordination orientée vers la photosynthèse artificielle ainsi que le développement de matériaux fonctionnels démontre l’importance indéniable de ce champ de recherche. Ce travail présente dans un premier temps l’étude des différentes voies de synthèse d’hydroxyamidines, un ligand chélatant aux propriétés de coordination prometteuses ne recevant que très peu d’attention de la part de la communauté scientifique. Dans un deuxième temps, nous présenterons le développement d’une stratégie d’assemblage de leurs complexes supramoléculaires impliquant des métaux de transition abondants et peu dispendieux de la première rangée. Dans un troisième temps, il sera question de l’investigation de leurs propriétés photophysiques et électrochimiques à des fins d’applications au sein de matériaux fonctionnels. Pour ce faire, les différentes voies de synthèse des hydroxyamidines et de leurs amidines correspondantes qui ont précédemment été étudiées par les membres du groupe seront tout d’abord perfectionnées, puis investiguées afin de déterminer leur versatilité. Ensuite, les propriétés de complexation des amox résultantes comportant des motifs sélectionnés seront déterminées pour enfin étudier les propriétés photophysiques et électrochimiques d’une série de complexes de métaux de transition de la première rangée. En somme, plusieurs designs qu’offrent les amox et bis-amox sont étudiés et les propriétés des architectures résultantes de leur auto-assemblage sont déterminées. / In a context where energy supply represents a major challenge for countries and organizations with emerging and developed economies, the search for new renewable resources and the democratization of energy vectors allowing sustainable worldwide supply is a responsibility for the international scientific community. Besides, it would be essential that the many disciplines of chemistry concerted their efforts. In particular, the growth of research in coordination chemistry oriented toward artificial photosynthesis and the development of functional materials demonstrates the undeniable importance of this field of research. The first part of the work presents different synthetic routes to hydroxyamidines, a chelating ligand with promising properties and receiving very little attention from the scientific community. Secondly, we present the development of a strategy of assembly of their supramolecular complexes involving abundant and cheap first row transition metal. Thirdly, we will discuss the investigation of their photophysical and electrochemical properties for their purposes in functional materials applications. To do this, the different synthesis routes of hydroxyamidines and their corresponding amidines which have previously been studied by other members of the group will first be improved then investigated to determine their versatility. Next, the complexing properties of the resulting amox having selected patterns will be determined to finally study the photophysical and electrochemical properties of a series of first row transition metal complexes. In sum, the various designs offered by amox and the bis-amox complexes are studied and the properties of the resulting architectures of their self-assemblies are determined.